Asset Pipeline

@chadwpry looks like it's just a config setting

Starting with version 3.1, Rails defaults to concatenating all JavaScript files into one master .js file and all CSS files into one master .css file. As you’ll learn later in this guide, you can customize this strategy to group files any way you like. In production, Rails inserts an MD5 fingerprint into each filename so that the file is cached by the web browser. You can invalidate the cache by altering this fingerprint, which happens automatically whenever you change the file contents..

Full article: http://guides.rubyonrails.org/asset_pipeline.html#customi...